Input devices, including proximity sensor devices (e.g., touchpads or touch sensor devices), are widely used in a variety of electronic systems. A proximity sensor device may include a sensing region, often demarked by a surface, in which the proximity sensor device determines the presence, location and/or motion of one or more input objects. Proximity sensor devices may be used to provide interfaces for the electronic system. For example, proximity sensor devices may be used as input devices for larger computing systems (e.g., opaque touchpads integrated in, or peripheral to, notebook or desktop computers). Proximity sensor devices are also often used in smaller computing systems (e.g., touch screens integrated in cellular phones).
Proximity sensor devices are subject to interference from a variety of external sources. Interference is the presence of noise in the sensing region that impedes the detection of input objects. For example, interference may be due to the display, through input objects at other locations, and other conductive sources. Interference may be persistent or intermittent. The presence of interference impacts the input device's ability to accurately detect and determine positional information for input objects. Thus, interference is managed. The technique to manage interference is dependent on whether the interference is persistent or intermittent.